Blood or sterile fluid equipment



March 12, 1957 E. J. POITRAS BLOOD OR STERILE FLUID EQUIPMENT 2 Sheets-Sheet 1 Filed Jan. 20, 1955 Fwd $1 M,

March 12, 1957 E. J. PorrRAs BLOOD OR STERILE FLUID EQUIPMENT 2Sheets-Sheet. 2

Filed Jan. 20, 1955 United States Patent ce BLOOD 0R STERILE FLUIDEQUIPMENT Edward J. Poitras, Holliston, Mass. Application January 20,1955, Serial No. 483,071 4 Claims. (Cl. 249-3) This invention relates tomedical and surgical apparatus. More particularly it aims to provideblood and other sterile fluid collecting equipment whereby the flow ofblood from a donor or of intravenous and the like sterile fluids from asupply is automatically controlled and shut off when a determined amounthas been obtained.

In the drawings illustrating by way of example one embodiment ofapparatus of the invention:

Fig. 1 is a relatively small-scale elevational view of the same in usewith a blood donor;

Fig. 2 shows the equipment of Fig. l on a larger scale, in the initialopen or starting position;

Fig. 3 is a view like Fig. 2 but with the flow tube automatically shutOE With the desired quantity of blood in the collecting vessel; and

Fig. 4 is a top plan of the apparatus of the preceding figures.

An important use for the therapeutic apparatus of the invention is inblood donation, represented in Fig. 1 as one example of medical,surgical and hospital fluid handling to which the invention ispertinent. Fluid as herein referred to includes intravenous and othersterile fluids in the therapeutic field as well as blood and bloodpreparations and other fluids.

The illustrated equipment includes a suitable fluidas at the port 3. Theother end is connected to the fluid supply source, as by a hypodermicneedle 11 for insertion in the arm of a donor D, in the case of bloodcollection. For subsequent sterile access to and use of the contentfluid the bag 1 has one or more sealed and sterilesheathed outlets 4including projecting tab-like portions affording convenient hangerconnection as at an eye 5. In the practice of this invention thecontainer or bag 1 and the donor-connectible tube 2 are operativelypositioned upon and by automatic flow control and limiting means asexemplified in the several views.

Such comprises a fixture or stationary support shown as a standdesignated generally at 6 presenting at a suitable height a mountingpost 7 for a head or bearing block 8 adjustably held thereon as by a setscrew 9, Fig. 4. A lateral boss or stud 10 on the head 8 provideshorizontal pivotal support for a two-arm tiltable lever desig nated as awhole at 11 and comprising at opposite sides of said pivot 10 acontainer-supporting or bag arm 12 and a counterbalance or weight arm13.

The fluid-collecting bag 1 is' adapted to be hung at the outer portionof the bag arm 12 as by a button 14 on. the latter receivable in thementioned hanger eye 2,784,932 Patented Mar. 12, 1957 provided for thepurpose on the bag. Such button or other suspending member 14 may beadjustable along the arm for regulating purposes. The other lever arm 13carries at the outer end an adjustable counterbalance or weight 15 hungthereon as at one of a series of selectable holes or other attachingformations 16. Such weight is selected and adjusted, as by interchangeof weight members, by adding or substracting small masses, or bychanging the weight-attaching position along the arm 13, as appropriatefor the given therapeutic fluid collecting operation.

It will be understood that the weight of the bag 1 and of the supportedportion of the tubing 2 for a given operation and size of bag, isuniform. The correct weight setting for the apparatus accordingly may bepredetermined for the amount of blood or other fluid to be collected,taking into consideration any initial content of the bag such as certainanti-coagulant material sometimes placed in it in the case of bloodcollection. Hence a standard setting of the apparatus is available forrepeat operations of the given character, such as the usual taking of500 cc. of blood from a human donor. The apparatus may be calibrated andreadably marked, on the lever arm or elsewhere, as appropriate for agiven fluid collection, such as that mentioned.

The automatic fluid content control and limiting ap paratus of theinvention further comprises means for disposing the inlet tube 2 topresent an intermediate portion thereof for pinch closure and yet toafford free flow therein during the collecting procedure, while alsoavoiding introduction of any factor tending to bias the reading of theapparatus. Accordingly an intermediate portion of the tube 2 is arrangedto present a bight 2a thereof, Figs. 2 and 3, at and around the leverpivot 10 and such that the tubing will enter the control arm 11 at thepivot 10 and be able to flex thereat with the arm and thus be free frompull attendant on arm movement.

For this purpose suitable tubing guide means is provided at oppositesides of the lever pivot 10. Such means includes a first and fixed guideand holder member 20 on the stationary head 8, herein somewhat above andbehind said pivot 10. This guide 20 shown as a boss or stud on the headShas a tube holding guide slot formation including a laterally open mouth21 admitting to a tubing-conformant guide portion 22 of interruptedcircular cross-section. The guide mouth 21 is adapted to retain thetubing 2 upon lateral entrance into the guide portion 22, being shown asnarrowed to less than the outer diameter of the resilient-walled tubing,but permits the latter easily to be set into and later removed from thisslotted guide means 20-22. As seen in Figs. 2 and 3 the opposite endortions of this guide formation, in the direction paralleling thetubing, may be flared or rounded to' facilitate mounting and guidance ofthe tubing.

The tubing guide means further includes at the opposite side of thelever pivot 10 a similar tubing guide member 25 having a mouth 26 andretainer slot 27 but in this instance positioned on and moving with thebag arm 12 of the lever 11. The plurality of tube holding guides 2022and 25-27 is positioned relative to each other and to the arm pivot 10as appropriate to define and present a bight 2a. of the tubing passingto and around said pivot point 10. Hence the respective guide slots 22and 27 are disposed in general line with the path desired for thecorresponding leg of such tubing bight 2a. As shown they stand atopposite sides of a generally vertical line through the arm pivot 10,and, at least in the starting of the apparatus, Fig. 2, upon the sameside of a generally horizontal line through said arm pivot. Accordinglythe plural guide means holds and presents the tube 2 in an open loop orbight such as 2a. The tube guides 20, 25 and the arm pivot 10 also areso correlated in position that the end of the tubing is non-constrictiveof flow in the tubing yet the bight 2a is presented closely around thearm pivot 19 and in such manner that the tubing in effect enters thelever arm at the pivot point with the latter adapted to serve as afulcrum for the flexing of the tube, or the outgoing leg of the bightthereof, attendant on pivotal tilting movement of'the lever 11. Thus thetube 2 is directed in its approach to and departure from the pivot 19along a bend or curved path consistent with unconstricted flow of fluidthrough the tube. As further facilitating this arrangement thepivotdefining boss or stud 10 preferably has a tube-guiding concentriccircumferential groove or guide channel 10x, Fig. 4, similar to that ofa rope pulley, integrally or otherwise formed on the pivot boss or stud10 as by threading a headed stud member 17 into it at the pivot axis. Aninner flange on such member may serve as a retaining collar for thelever arm 11.

In the foregoing description of the tubing guide means and the formingand location of the tubing bight 2a the latter merely for purposes ofdisclosure is treated as generally upright and open at the top and thereference lines for the guides are for identification called vertical"and horizontal. The tubing bight may be otherwise positioned about thepivot axis 10, inversely to that shown or in some intermediate positionaround the pivot, said reference lines then being correspondinglydisposed radially of the pivot and generally perpendicular to eachother. Also, while the position length of tubing 2a entering the leverarm at the pivot thereof is referred to as a bight it should beunderstood that the degree of curvature or bend may be less or more thanthat shown and may range widely between substantially a zero curva--ture and 360 of arc. Some degree of bend is generally found desirable,to slack the tubing at the arm pivot region and prevent undue tension orother effect thereon apt to bias the apparatus reading.

The invention further comprises automatic shut-elf means associated withthe tubing bight and the parts already described. Such means isillustrated as a pinch valve or clamp device and includes a fixed memberor anvil 30 shown as a pin projecting from the stationary head 8 hereinbelow the tubing bight 2a, together with a cooperative movableconstrictor or nip member 31 on the bag arm 12 of the lever 11, withinthe tubing bight and at the opposite wall of the tubing. These clampmembers 3Q, 31 are disposed in opposed paired relation adjacent thelever pivot ltl. In the initial or starting position of Fig. 2 the tube2 passes uninterruptedly between said clamp members. In thepredeterminedly loaded position of Fig. 3 said valving clamp membershave closed upon the tubing with a positive and forceful nipping actionsuch that the inner wall of the tube is collapsed upon itself across afull diameter and fluid flow is completely cut off. For this purpose oneor both of the pinch valve members 30, 31, herein the movablearm-carried member 31, is formed with an angular nose or corner portion32 adapted to define a cross-sectional zone or line of pinch-01fengagement across the tubing 2.

The relative proportioning and positioning of the described partsincluding the supporting lever 11, its pivot point 10 and the pinchvalve elements 30, 31 are so calculated that the desired automaticshut-off action, which is had without introduction of any external forcebeyond that of gravity, takes place in a definite and positive fashion,with rapidly increasing force application and with a force multiplyingand toggle-like action at the region of the cut-off. As apparent inFigs. 2 and 3 the bag arm 12 has an upward rake. The point of suspensionof the bag 1 thereon is such that in the descent of the bag arm 12 underpredetermined loading of the bag there is an increase in the effectivelength of the lever arm to an extent as indicated by the dotted lines aand b on Fig. 3. These represent respectively, in vertical projection,the horizontal distances of the bag suspension point from the leverpivot point 10 in the initial and the loaded or shut-otf positions ofthe bag.

In similar but opposite fashion the weight arm 13, also formed with anupward rake, undergoes a decrease in effective lever length as theweight 15 rises. Such upward leverage decrease is indicated on Fig. 3 bythe dotted lines 0 and d vertically projecting respectively the initialand the final positions of the weight-attaching point of the weight arm13 relative to a horizontal line through the lever pivot 10.

Hence the closing-oi down-travel of the bag 1 and fluid content as thepre-set load point arrives is adapted to exert increasing and quicklyand positively effective activation of the pinch valve with respect tothe in-flow tube 2.

Positive cut-off is still further assured by the force multiplicationand toggle-like action at the valve. First, the force-applying arm 12from the pivot 10 to the bag suspension point 14 is of a length greatlyexceeding and herein many times that of the work arm from the same pivotpoint to the pinch nose 32. Further, the toggle action is seen byregarding the nose 32 as the central or intermediate point of thetoggle. Then the toggle arms are represented by the dotted line xxjoining the arm pivot center 10 and said nose 32, and the line y-y at anangle to line xx and joining said nose 32 and the proximate point uponthe fixed or anvil member 30 of the clamp valve.

Now comparing Figs. 2 and 3 it is seen that the toggleangle between thelines xx and yy flattens in the course of the shut-off action. The nosemember 32 is thus in effect forcibly thrust in between the tworelatively fixed points or abutment members 10 and 30. Under this toggleeffect combined with the augmented leverage of the bag arm 12 itself asubstantial pinching force is exerted upon the engaged cross-sectionalzone of the tube 2 insuring the desired positive closure thereof at thepredetermined set point for the bag load. With the leverage system ofthe illustrative example an amplification of the shut-off force of theorder of 10 to 1 and higher may be had.

The initial position or up limit for the bag arm 12 is determined by 21preferably adjustable stop 18 on the mounting head 8, above said arm.The described anvil or pin 30 provides an opposite or down limit forsaid arm.

From the foregoing description in connection with the exemplaryapparatus of the drawings, and in view of the toggle action for thepinch-ofl valve and the torque multiplication obtained by the relativeradii or lever arms 10-14 for the bag and 10--32 for the movable pinchvalve element, together giving more than ample force for securely andpromptly pinching off the donor tube 2, it is apparent that theinvention provides for certain and automatic cut-otf of the flow of theblood or other fluid by pinch-closing the flexible tubing 2 at thecorrect predetermined fluid quantity. This flow cutoif is self-energizedin the sense that it is accomplished without resort to external power inaid of gravity. Under the geometry of the illustrated leverage system anaugmented and substantial torque is developed when the proper weight offluid has been taken. Further, the construction and arrangement is suchthat the containersupporting arm 12 is caused to tilt through aconsiderable angle, making the loaded or cut-off position quicklyrecognizable and thus giving an easily noted indication to thephlebotomist or other fluid-collecting operator that the procedure hasbeen completed.

It will be understood that my invention, either as to means or method,is not limited to the exemplary embodiment or steps herein illustratedor described, and I set forth its scope in my following claims.

I claim:

1. Therapeutic fluid collecting apparatus comprising,

in combination with a closed container and flexible tubing leadingthereto from a fluid source, a fixture, a horizontally pivoted arm onthe fixtrre having means to attach such container at a point remote fromthe arm pivot, means to counterbalance the arm and container up to apredetermined fluid load for the latter, and opposed constrictor meanson the fixture and the arm having the tubing passed between them, saidconstrictor means and arm constructed and arranged for nip closure ofthe tubing by sudden gravitational down-swinging of the arm withincreasing mechanical advantage and torque at arrival of thepredetermined fluid load in the container.

2. Therapeutic fluid collecting apparatus comprising a stationarysupport, a two-arm lever movable thereon about a horizontal pivot, onearm of the lever having means for suspending a fluid-collecting closedcontainer having a length of flexible tubing delivering thereto, acounterbalance on the other lever arm, laterally open slip-in tubingholders at spaced points adjacent and at opposite sides of the leverpivot to present between them and around the lever pivot a bight of thetubing for pinch closure, a fixed anvil member, and a cooperable pinchmember moving with the lever, said members disposed at opposite walls ofthe tubing of said bight so as to there pinch close the tubing underdown-swinging of the lever upon predetermined fluid collection into thecontainer, and said lever arm at the container side having an angularouter portion upwardly directed in the filling position and servingautomatically to increase the mechanical advantage by eflfectivelylengthening said arm as it swings down and thereby producing positiveclosure of the tubing.

3. In the collection and handling of therapeutic fluids in containers,the method which comprises predetermining gross weight for the containerand desired fluid quantity, vertically movably suspending a container tobe loaded, flowing therapeutic fluid through flexible tubing from asupply into the container and continuing the flow until occurrence ofself-energizing descent of the container and fluid content, mechanicallymultiplying the descent force increasingly during the descent, andavailing of such force at a section of the tubing between the containerand the fluid supply positively to pinchshut the tubing and therebyautomatically to segregate the desired quantity of therapeutic fluid inthe container.

4. The therapeutic fluid collecting apparatus accord ing to claim 2wherein the lever arm at the counterbalance side also has an angularlyupwardly directed outer portion and further increases the mechanicaladvantage for positive tubing closure by effectively shortening saidcounterbalance arm as it rises under downswinging of the container arm.

References Cited in the file of this patent UNITED STATES PATENTS1,495,724 Blake May 27, 1924 FOREIGN PATENTS 231,795 Switzerland July17, 1944 867,290 Germany Apr. 13, 1953

